1. Field of the Invention
The invention is directed to a metallurgical process for the consolidation of powder, wherein the process involves the utilization of a split case die. The subject invention is also directed to a part produced from such a process.
2. Description of Related Art
Fabrication of cutting inserts from sinterable powder, i.e. metallurgical cermets or ceramic powders, involves compaction of the sinterable powder with or without a fugitive binder into a pre-sintered green part. Subsequent sintering of the green part produces a finished part which may be a cutting tool. Compaction takes place under high pressure obtained through large opposing forces generated by top and bottom rams urged into a die cavity formed in a die containing the sinterable powder.
U.S. Pat. No. 6,986,866 is directed to a method and apparatus for cross-hole pressing to produce cutting inserts, whereby a solid unified die having a die cavity within is utilized to produce a green part. The green part is ejected through the unified die cavity and, as a result, the shape of the green part is limited to a shape able to “slide” through and out of the die cavity.
United States Patent Application Publication No. US 2006/0165828 is directed to a method and apparatus for manufacturing a cutting insert, whereby a split case die is separable in a direction parallel to the pressing axis to produce a green part that would not be able to freely pass through the die cavity on either side of the green part. However, utilizing such an arrangement, the features on the side of the green part must be configured such that the die parts may slide over them to release the green part. Not only does this requirement dictate limitations on the shape of the green part but, furthermore, the die parts sliding over the green part introduce friction against the part that might damage the part.
A process and apparatus is needed for use in a pressing operation, whereby the shape of the green part is not subjected to release from the die by sliding through the die or by having die parts slide over the part.